1. Field of the Invention
The present invention relates to an apparatus for use with a sewing head for making a predetermined stitch pattern in juxtaposed material pieces, and more particularly, an apparatus whereby juxtaposed material pieces will be displaced in a manner determined by a pattern path formed by a toothed cam track and groove contained in the apparatus.
2. Description of Prior Art
In the field of contour stitching machines, there are generally two types of apparatuses, namely, electronically controlled or mechanically controlled machines. Electronically controlled carriage systems are fairly expensive as they operate with numerically controlled computers and move a carriage along an X--Y axis guided by the stored program in the computer. These type of electrical systems are quite complex and the present invention is not concerned with such, but to a mechanical solution which is more economical, and which provides the same advantages as an electronically controlled pattern stitching system.
As an example of prior art mechanical systems, reference is made to U.S. Pat. Nos. 3,276,405 to Scholl; U.S. Pat. No. 3,439,637 to Haselgrove et al; U.S. Pat. No. 3,440,980 to Bono; U.S. Pat. No. 3,653,347 to Bianchi; U.S. Pat. No. 3,757,711 to Junemann; U.S. Pat. No. 3,871,306 to Egtvedt et al; U.S. Pat. No. 3,872,807 to Palmer; and U.S. Pat. No. 4,038,932 to Drew.
Heretofore, the components forming the mechanical systems have included belt drives or chain drives which, although sufficient for light manufacturing purposes, have been found to be deficient for heavy manufacturing applications, e.g., in the case of sewing two components together as employed in automobile seating, where the number of components to be sewn is numbered in the millions. It has been found that prior art systems, because of their construction, and the number of components forming the system, break down and are not capable of high volume operations, such that they have a tendency to be clogged, jammed, and eventually are inoperative.